Benthic sediment conditions and remediation alternatives ...

APPENDIX B

1995 Sediment Core Survey (October 31 - November 1)
with 1985 (Bogner et al.) Cross-sectional Profiles

Data Collection: October 31 - November 1, 1995
Transect Number

Distance from Left Bank Looking Downstream (ft)

Transect #3

Transect #4

Transect #5

Transect #7

Transect #8

Transect #9

Transect #10

Transect #11

Transect #12

Transect #13

Transect #14

Black Creek Delta and Above Dam/Spillway
Coring Profiles

APPENDIX C

General Information on the EDDY Pump
Method of "Vacuum Dredging"

New Pump Application Cuts Cost of Dredging Reservoirs

PG&E's R&D and Hydro Genera­ two facilities. Exist­ The EDDY pump creates a vortex, or concentrated swirling
tion departments have joined to dem­ ing sediment de­ column of fluid, that forces sediment up along the sides of the
onstrate an innovative, cost-saving posits already par­ pump chamber and out a floating discharge hose running up-
method for removing sediment at tially obstruct key stream of the dam out of harm's way.
PG&E's Cresta and Rock Creek reser­ intake and outlet
voirs. The dredging method, which uses structures, and rur-
a device called an EDDY pump, could ther buildup will
provide a one-time savings of 510 mil­ threaten power gen­
lion compared with conventional eration. Also. be­
dredging techniques. If the demonstra­ cause of the high
tion is successful, Hydro could use the levels of deposits,
EDDY pump as pan of a comprehen­ sediments readily
sive sediment management plan for the pass into the power
reservoirs. runnel and through
the powerhouse.
"Sedimentation, which is the result The abrasiveness
of natural upstream erosion. has dis­ of the sediment has
placed about 50 percent of the original accelerated wear
storage capacities of these two reser­ and tear on tur­
voirs and is threatening reliable opera­ bines, increasing
tion of the dams and powerhouses," O&M costs by
says Larry Harrison, Hydro Generation approximately
project manager. 5100,000 annually.

Since the mid-1980s, PG&E has ex­ To remedy the
perienced operational problems at the situation, Hydro
Generation plans to.
We're moving... install additional
low-level outlets at
the base of each

On December 28, the offices of dam. These outlets will be opened dur­ demonstration of a novel dredging
the R&D Department will be ing periods of high flows, when most plan using the EDDY pump.
relocated to 2303 Camino sedimentation occurs, so waterborne
Ramon, Suite 200, San Ramon, sediment can pass through the dam in­ The EDDY pump, which was devel­
CA 94583. Our telephone stead of settling in the reservoir. oped and patented by Dr. Harry
numbers will remain the same. Weinrib of PBMK Consultants &
Prior to that installation, however, Engineers, operates on a physical prin­
the sediment now blocking existing ciple similar to that of tornadoes or
dam outlets must be removed. For this waterspouts (see figure). It creates
application, Hydro Generation invited an "eddy current," or concentrated
the R&D Department to co-sponsor a
(Continued on page 4)

83

Dredging

(Continued from page 1)

swirling column of fluid that forces the At Cresta reservoir, a portion of "The EDDY pump will be a key en­
abling technology for resolving
sediment up into a floating discharge the sediment now blocking the dam sediment problems in a low-cost way,"
says Felmir Singson, R&D project
hose that runs upstream of the dam, outlets—about 10,000 cubic yards— manager. "Since all our reservoirs are
affected by sediment to some degree,
where the material is redeposited out is being dredged. The resulting slurry I foresee a great many uses for this
technology. It's new technology such
o'f harm's way. (up to 60 percent solids by weight) is as EDDY pumps that will help Hydro
Generation stay on the leading edge as a
According to Harrison, the EDDY being moved about 1000 to 2000 feet competitive provider of electricity."

pump offers advantages over conven­ upstream of the dam. Over the years, For more information contact Felmir
Singson. R&D project manager. (510)
tional techniques. It is cleaner, faster during periods of high flow, this 866-5469. ■

and less costly redepos­ The PG&E Research Reporter is
published quarterly by Pacific Gas
than clam­ ited sedi­ and Eiectric Company's Research and
Development (R&D) Department.
shell dredg­ The EDDY pump will be a key enabling ment will under Garth Hall. department
ing, which technology for resolving sediment be flushed manager. Dick Davin is editor;
generally problems in a low-cost way. Since all out of the Contributing editors include Jonas
involves low­ PG&E reservoirs are affected by sediment reservoir Weisel and Kathy McMorrow.
ering a clam­ to some degree, the pump will be put to a through the Subscriptions are free and can be
shell bucket great many uses. new dam obtained by writing to the R&D Report
into a stream outlets. Center. R&D Department. PG&E. 2203 .
Carr.ino Ramon, Suite 200. San
to dig up sedi­ A re- Ramon. CA 94583.

ment, placing search Pnnted on recycled pacer

the sediment on a barge, and draining monitoring plan has been
it for cransport to a land site. Because developed to validate the expected
the new technology stirs up the benefits of the technology and ensure
streambed to a lesser extent, it also has that the pump meets strict require­
fewer adverse environmental impacts ments for water quality. Features such
on water quality and aquatic habitat. as turbidity and re-suspension of sol­
ids and oil into the water will be
Compared to centrifugal pumps, the monitored. If the demonstration con­
EDDY pump is less costly and cleaner firms the feasibility of the EDDY
because it moves less water, transport­ pump dredging strategy, Hydro may
ing a dense slurry the consistency of use the pump to remove an additional
cake batter, and is more productive 125,000 cubic yards of sediment at
because its efficiency is not degraded the dams.
by abrasive wear or clogging.

R&D Department Bulk Rate
PG&E U.S. Postace
2303 Camino Ramon, Suite 200
San Ramon, CA 94583 PAID

Santa Rosa. CA
Permit No. 375

Clark W. B u l l a r d
Dept. of Mechanical Eng.
1206 W. Green S t .
Urbana IL 51801

84

Region V Review of George Lake Clean Lakes Diagnostic-Feasibility Study

PUBLIC ACCESS

Calumet College owns the lake bottom, the lake water and a portion of the land adjacent to the
lake. Calumet College President Dennis Rittenmeyer has stated publicly, and allegedly, in
writing, that the college will continue their current policy of providing public access to the lake,
and the lake waters, should the college retain ownership of the lake. President Rittenmeyer has
also publicly stated that Calumet College will continue to hold title to land adjacent to the lake's
east shoreline, and that the College would permit public access to the water's edge, should the
lake be sold (George Lake is currently available for sale, and a prospective buyer has purchased
an option to buy the lake).

Should Calumet College sell the lake and provide public access to the lake from their property on
the eastern shore, there is no legal leverage to require the new owner, who will have obtained
title to the lake water and lake bottom, to provide the public access to the waters of the lake.
This would then counter both the spirit and the letter of the Clean Lakes Program Regulations
requirements for public access, at 40CFR part 35.1605-3.

HEALTH OF THE FISHERY

1.) During the September 17, 1996 public hearing for the George Lake Diagnostic-Feasibility
Study, Dennis Wesolowski pointed out that the U.S. Fish and Wildlife Service Biological Report
of Fish Residue (July 1995) revealed elevated levels of polynuclear aromatic hydrocarbons
(PAHs) in the bile of bullheads; however, the Diagnostic-Feasibility Study did not investigate
concentrations of PAHs in the lake sediment, a likely source of the fish bile contaminant The
potential role of sediment PAHS as an ongoing hazard to fish health in the lake should be
clarified.
Without this data, it is difficult to project the future health of the bullhead fishery, or the impact
of any dredging on the fishery, or on water quality.

(The study contractor did request supplemental funding for this task after initiating work on the
project, and then discovering the need for PAH sediment data. However, we were not able to
obtain additional funding for the project)

2.) The Indiana Department of Environmental Management recently revised their criteria for fish
consumption advisories. As a consequence, your agency issued the following advisory for
Northern Pike obtained from George Lake, based on concentrations of polychlorinated